Endemic Toxin Variant Clostridium Difficile in an Irish Teaching Hospital

Predominance of PCR-ribotypes, 018 (smz) and 369 (trf) of Clostridium difficile in Japan: a potential relationship with other global circulating strains?

“…In contrast, the emergence of A 2 B + isolates, which have 1.8 kbp deletions in the repeating sequences in tcdA and belong to toxinotype VIII, has been reported in Japan as well as the Netherlands, Ireland, Poland, Korea, China and Argentina (Kuijper et al, 2001;Komatsu et al, 2003;Drudy et al, 2007;Shin et al, 2008;Goorhuis et al, 2009, Kato et al, 2010Pituch et al, 2011;Hawkey et al, 2013). The reports from all these countries, except Japan, documented that the vast majority of these A 2 B + isolates were found to be of PCR-ribotype 017 (Kuijper et al, 2001;Drudy et al, 2007;Goorhuis et al, 2009;Pituch et al, 2011;Hawkey et al, 2013;Lee et al, 2014).…”

“…Also, PCR-ribotype 018 was reported to be a predominant strain in Korea (Han et al, 2014). On the other hand, the emergence of toxin A-negative, toxin B-positive (A 2 B + ) C. difficile has been noted in the Netherlands, Ireland, Poland, Korea, China and Argentina (Kuijper et al, 2001;Drudy et al, 2007;Shin et al, 2008;Goorhuis et al, 2009;Pituch et al, 2011;Hawkey et al 2013), and in some of these reports the resistance of PCR-ribotype 017 (A 2 B + ) to clindamycin was documented (Kuijper et al, 2001;Goorhuis et al, 2009;Pituch et al, 2011). It was reported that differences in strain types have an impact not only on epidemiology but also on the course of treatment and laboratory diagnosis (Tenover et al, 2010;Louie et al, 2011).…”

The host immune response to Clostridium difficile

“…Studies using human colon have shown that toxin B is a more potent enterotoxin than toxin A in human colon (Riegler et al, 1995;Savidge et al, 2003). Furthermore, human strains of toxin A-negative, toxin Bpositive C. difficile have emerged which have been associated with sporadic and epidemic CDI (Drudy et al, 2007). Taken together, these findings suggest that toxin B plays an important role in the pathogenesis of CDI, but do not disprove the role of toxin A in human disease.…”

New types of toxin A-negative, toxin B-positive strains among clinical isolates of Clostridium difficile in Australia

“…One particular clindamycin-resistant strain of apparent clonal origin (toxinotype VIII, PCR ribotype 017) has dominated international typing studies of A 2 B + and been the cause of epidemics in Canada, the Netherlands, Ireland and Poland (Alfa et al, 2000;Drudy et al, 2007;Kuijper et al, 2001;Pituch et al, 2007). Although the frequency of A 2 B + strains in our collection was similar to that observed elsewhere , they were surprisingly heterogeneous with only two strains belonging to ribotype 017.…”

“…These strains were initially thought to be non-toxigenic as they were isolated from asymptomatic individuals and did not cause disease in a mouse model of infection (Borriello et al, 1992). Subsequently, clinically relevant toxin Anegative, toxin B-positive (A 2 B + ) strains have been well described in humans (Alfa et al, 2000;Drudy et al, 2007;Kuijper et al, 2001;Pituch et al, 2001;Sato et al, 2004) and animals (Thakur et al, 2010). There is also evidence that the prevalence of clinically significant A 2 B + strains may be increasing (Goorhuis et al, 2009).…”